Effect of polymer surface

The Effect of Polymer Surface Morphology on Adhesion and Adhesive Joint Strengths... 

At present, the protein/surface interactions that determine adsorption kinetics are unclear. To clarify these interactions, the effects of polymer surface properties on protein adsorption and desorption rates have been investigated. BSA adsorption from a 1 mg% solution (1 mg% = 1 mg/100 mL) was studied using several polymers chosen for their wide range of surface properties and functionalities (22, Cheng, Y.L. et al.. J. Coll. Int. Sci., in press). The polymers and their surface properties (under the conditions of the BSA adsorption experiments) are listed in Table I. 

Schonhom, Harold, Ryan, Frank W. (1969), "Effect of Polymer Surface Morphology on Adhesion and Adhesive Joint Strength. II. FEP Teflon and Nylon 6", J. Polym. Sci. 7 (Part A-2), 105-111 (Hara, K., Schonhom, H. (1970), "Effect on Wettability of FEP Teflon Surface Morphology", J. Adhesion 2, 100-105. 

Courtney JM, Lamba NMK, Sundaram S, Forbes CD (1994) Biomaterials 15 737 Salzman EW (1986) Blood material interaction In Interaction of tbe blood with natural and artificial surfaces, Dekker Inc, New York, p 39 Meyer JG (1986) Blutgerinnung und Fibrinolyse, Deutsche Arzte Verlag, Koln Baszkin A (1986) The effect of polymer surface composition and structure on adsorption of plasma proteins. In Dawids S, Bantjes A (eds) Blood compatible materials and their testing. Martinus Nijhoff Publishers, Dortrecht, p 39... 

The corona-treated PE surfaces were used to study the effect of polymer surface wettability on cell adhesion and growth. Chinese hamster ovary (CHO) cells (CHO-KI-BH4, Oak Ridge National Laboratory, USA) were used as a model system because they exist as reasonably stable single cells and are not unreasonably fastidious in terms of culture requirements (21). They are grown in monolayer with fast generation time (about 12 hr). 

Rios PF, Dodiuk H, Kenig S, McCarthy S, Dotan A (2007) The effect of polymer surface on the wetting and adhesion of Uquid systems. J Adhesion Sci Technol 3-4 227-242... 

Poljraer surfaces can be easily modified with microwave or radio-frequency-energized glow discharge techniques. The polymer surface cross-links or oxidizes, depending on the nature of the plasma atmosphere. Oxidizing (oxygen) and nonoxidizing (helium) plasmas can have a wide variety of effects on polymer surface wettability characteristics (92). 

Treatment of polymer surfaces to improve their wetting, water repulsion, and adhesive properties is now a standard procedure. The treatment is designed to change the chemistry of the outermost groups in the polymer chain without affecting bulk polymer properties. Any study of the effects of treatment therefore requires a technique that is specific mostly to the outer atomic layers this is why SSIMS is extensively used in this area. 

A very similar effect of the surface concentration on the conformation of adsorbed macromolecules was observed by Cohen Stuart et al. [25] who studied the diffusion of the polystyrene latex particles in aqueous solutions of PEO by photon-correlation spectroscopy. The thickness of the hydrodynamic layer 8 (nm) calculated from the loss of the particle diffusivity was low at low coverage but showed a steep increase as the adsorbed amount exceeded a certain threshold. Concretely, 8 increased from 40 to 170 nm when the surface concentration of PEO rose from 1.0 to 1.5 mg/m2. This character of the dependence is consistent with the calculations made by the authors [25] according to the theory developed by Scheutjens and Fleer [10,12] which predicts a similar variation of the hydrodynamic layer thickness of adsorbed polymer with coverage. The dominant contribution to this thickness comes from long tails which extend far into the solution. 

Polymerizations Above Tg. Let the polymerization begin in pure monomer. As the concentration of polymer chains increases initially one observes a relatively small increase in the termination rate constant. This is related to the effect of polymer concentration on coil size. A reduction in coil size increases the probability of finding a chain end near the surface and hence causes an increase in k-. Soon thereafter at conversions 15-20 polymer chains begin to entangle causing a dramatic reduction in radical chain translational mobility giving a rapid drop in k-j. ... 

Surface fluorination changes the polymer surface drastically, the most commercially significant use of polymer surface direct fluorination is the creation of barriers against hydrocarbon permeation. The effectiveness of such barriers is enormous, with reductions in permeation rates of two orders of magnitude. Applications that exploit the enhanced barrier properties of surface-fluorinated polymers include (1) Polymer containers, e.g., gas tanks in cars and trucks, which are produced mostly from high-density polyethylene, where surface fluorination is used to decrease the permeation of fuel to the atmosphere and perfume bottles. (2) Polymeric membranes, to improve selectivity commercial production of surface-fluorinated membranes has already started.13... 

Following the arguments by Van Loosdrecht et al. (1990) schematically the interaction between the (negatively charged) cell surface and the solid surface - a sulphated polystyrene surface (hydrophobic, negatively charged) - in presence of polymers, that have adsorbed to both surfaces can be shown to be caused by various interaction energies between the two partially or totally polymer-coated surfaces (Fig. 7.19). The effects of polymers have been interpreted (Van Loosdrecht et al., 1990) as follows ... 

It was observed elsewhere that plasma treatment of polymer macromolecules results in their cleavage, ablation, alterations of chemical structure and thus affects surface properties e.g. solubility [75]. The effects of the treatment in Ar plasma on the surface properties of PE were examined in [72]. The parameters of the plasma discharge (240 s, 8.3 W power) were chosen, on the basis of our previous experiments [70-74,78], to guarantee the most pronounced changes of polymer surface. Mean thickness of the ablated PE layer was calculated from the weight difference measured by gravimetry. By Ar plasma (8.3 W, 240 s) 30 8 nm thick surface layer is ablated and thickness of the surface layer removed from plasma-modified PE by 24 hour water etching is 21 5 nm [78]. 

Ko, Y.S., Forsman, W.C. and Dziemianowicz, T.S. (1982). Carbon fiber-reinforced composites effect of fiber surface on polymer properties. Polym. Eng. Sci. 22, 805-814. 

Figure 7 shows the effect of polymer dose on the measured zeta potential. Zeta potential continues to rise quite steeply through regions 1 and 2, but then decreases rapidly in region 3. This sharp decrease could be a result of the reduction in ionisation of the polymer as the adsorption density rises however, recently published studies on tethered polyacrylate chains at various surface... 

Pantoustier, N., Alexandre, M., Degee, P, Calberg, C., Jerome, R., Henrist, C., et al. (2001). Poly(3-caprolactone) layered silicate nanocomposites effect of clay surface modifiers on the melt intercalation process. e-Polymer, 9, 1-9. 

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